ST-10M – Mono Power Amplifier

ST-10M – Mono Power Amplifier


The ST-10M Mono Power Amplifier builds upon NuPrime’s fourth generation (V4) amplifier module from the ST-10 and brings it to the next level. The ST-10 was designed within the space limitation of its chassis and hence had a power system which was capable of providing 150W power output to each of the stereo channels. To really bring out the best of the V4 amplifier module, the ST-10M has a new 300W power supply for its mono channel. The entire design including the chassis has been optimised for the mono configuration, further lowering the cross channel interference.

Add to Wishlist
Add to Wishlist


The ST-10M Mono Power Amplifier sees the original 10A bridge rectifier replaced by a 50A Schottky diode, the capacitors upgraded to 30,000 micro-Farad, and duly the power transformer is now rated at 300W. Throughout the ST-10M an improved circuit layout has been achieved with careful component selection that has resulted in a lower noise floor than the ST-10 Stereo Power Amplifier.

The NuPrime Sound

The ST-10M delivers a more full bodied and rich sonic performance, it conveys greater immediacy and power as compared to the ST-10. The improved power delivery and reduced interference gives the instruments richer overtones and more natural decay. The soundstage is deeper and creates a greater sense of space. The imaging of the ST-10M more solid.

The improvements are demonstrable. The striking of piano keys arrives with greater attack and faster transients, a sound that naturally resonates with the piano body. Brass instruments sound glorious, characterful and carry a natural sheen without ever being “bright”. Female vocals and high frequencies retain the signature of the ST-10 but they arrive in a smoother, more refined fashion through the ST-10M. In an ensemble, the tonality gains an extra notch of richness which makes the overall presentation more natural.

With the ST-10M, every aspect of the ST-10 sound has been improved upon, pushing the ST-10M into reference grade territory.


  • Inputs:
    • RCA: Un-Balanced input x 1
    • XLR: Balanced input x 1
  • Outputs:
    • Speaker Out x 1
  • Power Output (rated): 230W @ 8 Ohms, 320W @ 4 Ohms
  • Power Output (peak): 270W @ 8 Ohms, 375W @ 4 Ohms
  • Gain: x 28
  • Input Impedance: 47k Ohms
  • Sensitivity: 1.5Vrms to rated power
  • Total Harmonic Distortion (THD): 0.01%
  • Signal to Noise Ratio (SNR): 91dB @ 10W
  • Frequency Response: 0Hz to 50kHz (-3dB)
  • Standby Power Consumption: 0.9W at 115V outlet, 1.7W at 230V outlet
  • Idle Power Consumption: 14W at 115V outlet, 14.8W at 230V outlet
  • Worldwide AC voltage: (115 VAC / 230 VAC) with Voltage Select Switch
  • AC Fuse: Slow-blow, 5A, 250VAC
  • Colour: High quality Anodised Black or Silver
  • Dimension: 59 mm x 215.4 mm x 394 mm  [W x H x D]
  • Weight: 6 kg

ST-10M is a phase inverting amp. If you are certain that the +/- (usually the red/white connectors) phase of your inputs are non inverting, then you should reverse the +/- inputs for each channel on ST-10M.  All other NuPrime amps were designed as non-inverting amp.  If you have no idea what this is all about, don’t bother with making any adjustment.

There is no 12V trigger for ST-10M.


User Manual
Manufacturer Website